Among the technologies concerning the collection or separation of gases that are being developed pursuant to their objective and use, separation/collection technology of carbon dioxide is becoming important from the perspective including the issues of global warming.
In the methods of collecting carbon dioxide from dry gas, adsorbents of porous materials such as silica gel, alumina, zeolite, activated carbon, and diatomite, as well as silica, calcium oxide, sodium oxide, potassium oxide, iron oxide and the like are being used (refer to Patent Documents 1 and 2).
Moreover, mostly, in the pressure swing adsorption methods of carbon dioxide, zeolite 13X is being used as the adsorbent (refer to Non-patent Document 1). Zeolite 13X yields a superior adsorption amount of carbon dioxide in a range of roughly 0 to 2 atmospheres. Nevertheless, in order to desorb the adsorbed carbon dioxide for use as an effective pressure swing adsorbent, there is a problem in that vacuuming needs to be performed and the pressure needs to be 0.2 atmosphere or less.    [Patent Document 1] Japanese Patent Application No. 2003-019435    [Patent Document 2] Japanese Patent Application No. 2005-040753    [Non-patent Document 1] Latest Adsorption Technology Handbook, Published by NTS (1999), Pages 133 to 140    [Non-patent Document 2] Goodman B. A. et.al. Phys. Chem. Miner. 12, 342-346 (1985)